Thermal aging at 475 °C of newly developed lean duplex stainless steel 2404: Mechanical properties and corrosion behavior

An investigation was made of the effect of aging for up to 2000 h at 475 °C on the properties of the newly developed lean duplex stainless steel (LDSS) 2404. Due to its lower alloying content, the degradation of corrosion resistance as a function of thermal aging evolves more slowly in LDSS 2404 than in a standard duplex alloy (DSS 2205). The results also suggest that the mechanism of α' phase formation in the ferritic matrix occurs by spinodal decomposition and that this phenomenon has a stronger impact on the steel's mechanical properties than on its corrosion behavior.